Equalizer constant velocity joints, which articulate or have angular displacement, can be either sliding joints, in which translational displacement occurs with a low sliding force, or fixed joints having no translational displacement. These joints use many of the same components and are specially suited for vehicle longitudinal drives. Their low friction characteristics, resulting from operating angles and longitudinal sliding, make equalizer constant velocity joints better suited to work well at high speeds than the constant velocity ball type joints used in wheel drive applications. Ball type joints operate at a lower speed and articulate through large angles in outboard joints in front wheel drive vehicle applications.
The fixed joint of this invention can be used in combination with a sliding joint, such as that disclosed in U.S. Pat. No. 6,120,381. The fixed joint of this invention functions similarly to the sliding joint, and can be used in both slip and fixed joint constructions, provided the outer race is suitably modified.
Equalizer constant velocity joints can be used in wheel drive applications in place of conventional ball type constant velocity joints. The fixed joint does not have the high angle capability for outboard steering angles required for front wheel drive applications.
Equalizer universal joints provide all of the desired characteristics that longitudinal drives provide for smooth, vibration-free operation. For example, constant velocity is produced with only the low inertia components turning non-uniformly when operating at an angle, and inertia forces are cancelled by out-of-phase motion. The joint's inherently low friction characteristics produce lower operating temperatures and longer life in high-speed drive applications. There is virtually no sliding friction due to length changes.
An assembly comprising a combination of a fixed joint and a sliding joint eliminates centering problems that could result if a slip joint were located at each end of the assembly. The fixed joint of this invention eliminates oscillating secondary couple loads at supports, as in fixed non-constant velocity joints, when transmitting torque through a joint angle. Many components of the sliding constant velocity joint described in U.S. Pat. No. 6,120,381 are identical to those of the fixed constant velocity joint of this invention, which would reduce the production cost of an assembly that includes in combination a fixed joint of this invention and a slip joint.